package com.example.lotterysystem.service.impl;

import com.example.lotterysystem.common.errorcode.ServiceErrorCodeConstants;
import com.example.lotterysystem.common.exception.ServiceException;
import com.example.lotterysystem.common.utils.JacksonUtil;
import com.example.lotterysystem.common.utils.RedisUtil;
import com.example.lotterysystem.controller.param.DrawPrizeParam;
import com.example.lotterysystem.controller.param.ShowWinningRecordsParam;
import com.example.lotterysystem.dao.dataobject.*;
import com.example.lotterysystem.dao.mapper.*;
import com.example.lotterysystem.service.DrawPrizeService;
import com.example.lotterysystem.service.dto.WinningRecordDTO;
import com.example.lotterysystem.service.enums.ActivityPrizeStatusEnum;
import com.example.lotterysystem.service.enums.ActivityPrizeTiersEnum;
import com.example.lotterysystem.service.enums.ActivityStatusEnum;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

import java.util.*;

import static com.example.lotterysystem.common.config.DirectRabbitConfig.EXCHANGE_NAME;
import static com.example.lotterysystem.common.config.DirectRabbitConfig.ROUTING;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: Li_yizYa
 * Date: 2025/8/20
 * Time: 19:27
 */
@Service
public class DrawPrizeServiceImpl implements DrawPrizeService {

    private static final Logger logger = LoggerFactory.getLogger(DrawPrizeServiceImpl.class);
    private final String WINNING_RECORDS_PREFIX = "WINNING_RECORDS_";
    private final Long WINNING_RECORDS_TIMEOUT = 60 * 60 * 24 * 2L; // 单位s

    @Autowired
    private RabbitTemplate rabbitTemplate;
    @Autowired
    private ActivityMapper activityMapper;
    @Autowired
    private ActivityPrizeMapper activityPrizeMapper;
    @Autowired
    private UserMapper userMapper;
    @Autowired
    private PrizeMapper prizeMapper;
    @Autowired
    private WinningRecordMapper winningRecordMapper;
    @Autowired
    private RedisUtil redisUtil;

    @Override
    public void drawPrize(DrawPrizeParam param) {

        Map<String, String> map = new HashMap<>();
        map.put("messageId", String.valueOf(UUID.randomUUID()));
        map.put("messageData", JacksonUtil.writeValueAsString(param));
        // 发消息: 1.发给哪个交换机  2.发给哪个队列(绑定的key)  3.消息体
        rabbitTemplate.convertAndSend(EXCHANGE_NAME, ROUTING, map);
        logger.info("mq消息发送成功: map:{}", JacksonUtil.writeValueAsString(map));

    }

    /**
     * 抛异常会存在 bug
     * @param param
     */
    @Override
    public Boolean checkDrawPrizeParam(DrawPrizeParam param) {

        ActivityDO activityDO = activityMapper.selectById(param.getActivityId());
        // 奖品是否存在，可以从 activity_prize 表中查询，原因是保存activity做了本地事务，保证一致性
        // 因为后续还需要判断奖品数量，所以直接从activity_prize表中查询即可
        // activityId 和 prizeId 组成了一个唯一索引
        ActivityPrizeDO activityPrizeDO = activityPrizeMapper.selectByAPId(
                param.getActivityId(), param.getPrizeId());

        // 活动或者奖品是否存在
        if (activityDO == null || activityPrizeDO == null) {
            // throw new ServiceException(ServiceErrorCodeConstants.ACTIVITY_OR_PRIZE_IS_EMPTY);
            logger.info("校验抽奖请求失败! 原因:{}", ServiceErrorCodeConstants.ACTIVITY_OR_PRIZE_IS_EMPTY.getMsg());
            return false;
        }

        // 活动是否有效
        if (activityDO.getStatus()
                .equalsIgnoreCase(ActivityStatusEnum.COMPLETED.name())) {
            // throw new ServiceException(ServiceErrorCodeConstants.ACTIVITY_COMPLETED);
            logger.info("校验抽奖请求失败! 原因:{}", ServiceErrorCodeConstants.ACTIVITY_COMPLETED.getMsg());
            return false;
        }

        // 奖品是否有效
        if (activityPrizeDO.getStatus()
                .equalsIgnoreCase(ActivityPrizeStatusEnum.COMPLETED.name())) {
            // throw new ServiceException(ServiceErrorCodeConstants.ACTIVITY_PRIZE_COMPLETED);
            logger.info("校验抽奖请求失败! 原因:{}", ServiceErrorCodeConstants.ACTIVITY_PRIZE_COMPLETED.getMsg());
            return false;
        }

        // 中奖者人数是否和设置奖品数量一致
        if (activityPrizeDO.getPrizeAmount() != param.getWinnerList().size()) {
            // throw new ServiceException(ServiceErrorCodeConstants.WINNER_PRIZE_AMOUNT_ERROR);
            logger.info("校验抽奖请求失败! 原因:{}", ServiceErrorCodeConstants.WINNER_PRIZE_AMOUNT_ERROR.getMsg());
            return false;
        }
        return true;
    }

    @Override
    public List<WinningRecordDO> saveWinnerRecords(DrawPrizeParam param) {
        // 查询相关信息: 活动、人员、奖品、活动关联奖品表
        ActivityDO activityDO = activityMapper.selectById(param.getActivityId());
        List<UserDO> userDOList = userMapper.batchSelectByIds(
                param.getWinnerList()
                        .stream()
                        .map(DrawPrizeParam.Winner::getUserId)
                        .toList());
        PrizeDO prizeDO = prizeMapper.selectById(param.getPrizeId());
        ActivityPrizeDO activityPrizeDO =
                activityPrizeMapper.selectByAPId(param.getActivityId(), param.getPrizeId());
        // 构造中奖者记录，保存(以中奖人为维度)
        List<WinningRecordDO> winningRecordDOList = userDOList.stream()
                .map(userDO -> {
                    WinningRecordDO winningRecordDO = new WinningRecordDO();
                    winningRecordDO.setActivityId(activityDO.getId());
                    winningRecordDO.setActivityName(activityDO.getActivityName());
                    winningRecordDO.setPrizeId(prizeDO.getId());
                    winningRecordDO.setPrizeName(prizeDO.getName());
                    winningRecordDO.setPrizeTier(activityPrizeDO.getPrizeTiers());
                    winningRecordDO.setWinnerId(userDO.getId());
                    winningRecordDO.setWinnerName(userDO.getUserName());
                    winningRecordDO.setWinnerEmail(userDO.getEmail());
                    winningRecordDO.setWinnerPhoneNumber(userDO.getPhoneNumber());
                    winningRecordDO.setWinningTime(param.getWinningTime());

                    return winningRecordDO;
                }).toList();
        winningRecordMapper.batchInsert(winningRecordDOList);

        // 缓存中奖者记录
        // 1、缓存奖品维度的中奖记录(key: WinningRecord_activityId_prizeId, winningRecordDOList(奖品维度的中奖名单))
        cacheWinningRecords(param.getActivityId() + "_" + param.getPrizeId(),
                winningRecordDOList,
                WINNING_RECORDS_TIMEOUT);

        // 2、缓存活动维度中奖记录(key: WinningRecord_activityId, winningRecordDOList(活动维度的中奖名单))
        // 当活动已完成再去存放活动维度中奖记录
        if (activityDO.getStatus()
                .equalsIgnoreCase(ActivityStatusEnum.COMPLETED.name())) {
            // 查询活动维度的全量中奖记录
            List<WinningRecordDO> allList = winningRecordMapper.selectByActivityId(param.getActivityId());
            cacheWinningRecords(String.valueOf(param.getActivityId()),
                    allList,
                    WINNING_RECORDS_TIMEOUT);
        }
        return winningRecordDOList;
    }

    @Override
    public void deleteRecords(Long activityId, Long prizeId) {
        if (activityId == null) {
            logger.warn("要删除中奖记录相关的活动id为空! ");
            return;
        }
        // 删除数据表
        winningRecordMapper.deleteRecords(activityId, prizeId);

        // 删除缓存(奖品维度的缓存、活动维度的缓存)
        if (prizeId != null) {
            deleteWinningRecords(activityId + "_" + prizeId);
        }
        // 无论是否传递了prizeId，都需要删除活动维度的中奖记录缓存
        // 如果传递了prizeId，证明奖品未抽奖，此时必须删除活动维度的缓存记录
        // 如果未传递prizeId，就只是删除活动维度的信息
        deleteWinningRecords(String.valueOf(activityId));
    }

    @Override
    public List<WinningRecordDTO> getRecords(ShowWinningRecordsParam param) {
        // 先查询 redis: 奖品维度、活动维度
        String key = param.getPrizeId() == null
                ? String.valueOf(param.getActivityId())
                : param.getActivityId() + "_" + param.getPrizeId();

        List<WinningRecordDO> winningRecordDOList = getWinningRecordDOList(key);
        if (!CollectionUtils.isEmpty(winningRecordDOList)) {
            return convertToWinningRecordDTOList(winningRecordDOList);
        }

        // 如果 redis 不存在，查库
        winningRecordDOList = winningRecordMapper.selectByActivityIdOrPrizeId(
                param.getActivityId(), param.getPrizeId());
        // 存放记录到redis
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            logger.info("查询的中奖记录为空! param:{}", JacksonUtil.writeValueAsString(param));
            return Arrays.asList();
        }
        cacheWinningRecords(key, winningRecordDOList, WINNING_RECORDS_TIMEOUT);
        return convertToWinningRecordDTOList(winningRecordDOList);
    }

    private List<WinningRecordDTO> convertToWinningRecordDTOList(
            List<WinningRecordDO> winningRecordDOList) {
        if (CollectionUtils.isEmpty(winningRecordDOList)) {
            return Arrays.asList();
        }
        return winningRecordDOList.stream()
                .map(winningRecordDO -> {
                    WinningRecordDTO result = new WinningRecordDTO();
                    result.setWinnerId(winningRecordDO.getWinnerId());
                    result.setWinnerName(winningRecordDO.getWinnerName());
                    result.setPrizeName(winningRecordDO.getPrizeName());
                    result.setPrizeTier(
                            ActivityPrizeTiersEnum.forName(winningRecordDO.getPrizeTier()));
                    result.setWinningTime(winningRecordDO.getWinningTime());
                    return result;
                })
                .toList();
    }

    /**
     * 从缓存中删除中奖记录
     * 此处 try catch 是因为不能让缓存是否成功来影响主流程
     * @param key
     */
    private void deleteWinningRecords(String key) {
        try {
            if (redisUtil.hasKey(WINNING_RECORDS_PREFIX + key)) {
                // 如果存在再去删除
                redisUtil.delete(WINNING_RECORDS_PREFIX + key);
            }
        } catch (Exception e) {
            logger.error("删除中奖记录缓存异常, key:{}", key);
        }
    }

    /**
     * 缓存中奖记录
     * 捕获异常，就算缓存失败，也不影响主流程
     *
     * @param key
     * @param winningRecordDOList
     * @param time
     */
    private void cacheWinningRecords(String key,
                                     List<WinningRecordDO> winningRecordDOList,
                                     Long time) {
        String str = "";
        try {
            if (!StringUtils.hasText(key) || CollectionUtils.isEmpty(winningRecordDOList)) {
                logger.warn("要缓存的内容为空! key:{}, value:{}",
                        key, JacksonUtil.writeValueAsString(winningRecordDOList));
                return;
            }
            str = JacksonUtil.writeValueAsString(winningRecordDOList);
            redisUtil.set(WINNING_RECORDS_PREFIX + key,
                    str,
                    time);
        } catch (Exception e) {
            logger.error("缓存中奖记录异常! key:{}, value:{}",
                    WINNING_RECORDS_PREFIX + key, str);
        }
    }

    /**
     * 从缓存中获取中奖记录
     * @param key
     * @return
     */
    private List<WinningRecordDO> getWinningRecordDOList(String key) {

        try {
            if (!StringUtils.hasText(key)) {
                logger.warn("要从缓存中查询中奖记录的 key 为空! ");
                return Arrays.asList();
            }
            String str = redisUtil.get(WINNING_RECORDS_PREFIX + key);
            if (!StringUtils.hasText(str)) {
                return Arrays.asList();
            }

            return JacksonUtil.readListValue(str, WinningRecordDO.class);
        } catch (Exception e) {
            logger.error("从缓存中查询中奖记录异常! key:{}", WINNING_RECORDS_PREFIX + key);
            return Arrays.asList();
        }
    }
}
